Add character in front and at the end of each character - sql

Question

In SQL I want to add 0 in front and , at the end of each character.
Example: A30F1 -> 0A,03,00,0F,01
I don't want to use cursor if possible.
Thanks!
EIDT:
I apologize for not asking the most appropriate question at the beginning.
In short, I have a table and for each value in the column name I have to convert it to the desired format. For example, we have a #Temp table:
CREATE TABLE #Temp (id INT, name VARCHAR(25))
INSERT INTO #Temp VALUES (1, 'A30F1'), (2, 'B51R9'), (3, 'L1721')
SELECT * FROM #Temp

Answer 1

One method would be to use a Tally to split the string into it's individual characters, and then use concatenation to add the 0 to the start, and STRING_AGG to comma delimit the results:
DECLARE #YourValue varchar(5) = 'A30F1';
WITH N AS(
SELECT N
FROM (VALUES(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL))N(N)),
Tally AS(
SELECT TOP (LEN(#YourValue))
ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) AS I
FROM N N1, N N2) --Up to 100 characters, add more cross joins for more characters
SELECT STRING_AGG(CONCAT('0',SS.C),',') WITHIN GROUP (ORDER BY T.I) AS NewString
FROM (VALUES(#YourValue))V(YourValue)
CROSS JOIN Tally T
CROSS APPLY (VALUES(SUBSTRING(V.YourValue,T.I,1)))SS(C);
It appears this is meant to be against a table, not a single value. This needs, however, very few changes to work against a table:
WITH N AS(
SELECT N
FROM (VALUES(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL))N(N)),
Tally AS(
SELECT TOP (SELECT MAX(LEN(YourColumn)) FROM dbo.YourTable)
ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) AS I
FROM N N1, N N2) --Up to 100 characters, add more cross joins for more characters
SELECT STRING_AGG(CONCAT('0',SS.C),',') WITHIN GROUP (ORDER BY T.I) AS NewString
FROM dbo.YourTable YT
JOIN Tally T ON LEN(YT.YourColumn) >= T.I
CROSS APPLY (VALUES(SUBSTRING(YT.YourColumn,T.I,1)))SS(C)
GROUP BY YT.YourColumn;
db<>fiddle

Answer 2

I solved the simplest possible with a few variables, WHILE and SUBSTRING
DECLARE #var VARCHAR(20) = 'A30F1', #i INT = 1, #res NVARCHAR(20)
WHILE (#i <= LEN(#var))
BEGIN
SET #res = #res + '0' + SUBSTRING(#var, #i, 1) + ','
SET #i = #i + 1
END
SELECT LEFT(#res, LEN(#res) - 1) output
Check demo on DB<>FIDDLE.

Answer 3

Original answer:
A recursive CTE and a STRING_AGG() call is also an option (SQL Server 2017+ is needed):
DECLARE #text varchar(max) = 'A30F1';
WITH rCTE AS
(
SELECT 1 AS CharacterPosition, SUBSTRING(#text, 1, 1) AS Character
UNION ALL
SELECT CharacterPosition + 1, SUBSTRING(#text, CharacterPosition + 1, 1)
FROM rCTE
WHERE CharacterPosition < LEN(#text)
)
SELECT STRING_AGG('0' + Character, ',') WITHIN GROUP (ORDER BY CharacterPosition)
FROM rCTE
OPTION (MAXRECURSION 0);
Update:
You need a different statement, if the names are stored in a table, again using recursion and STRING_AGG():
Table:
CREATE TABLE #Temp (id INT, name VARCHAR(25))
INSERT INTO #Temp VALUES (1, 'A30F1'), (2, 'B51R9'), (3, 'L1721')
Statement:
; WITH rCTE AS (
SELECT
t.id AS id,
LEFT(t.name, 1) AS Character,
STUFF(t.name, 1, 1, '') AS CharactersRemaining,
1 AS CharacterPosition
FROM #Temp t
UNION ALL
SELECT
r.id,
LEFT(r.CharactersRemaining, 1),
STUFF(r.CharactersRemaining, 1, 1, ''),
CharacterPosition + 1
FROM rCTE r
WHERE LEN(r.CharactersRemaining) > 0
)
SELECT
id,
STRING_AGG('0' + Character, ',') WITHIN GROUP (ORDER BY CharacterPosition) AS name
FROM rCTE
GROUP BY id
OPTION (MAXRECURSION 0);
Result:
id name
1 0A,03,00,0F,01
2 0B,05,01,0R,09
3 0L,01,07,02,01

Answer 4

If you are only applying this to English alphabet characters and digits as in your example you could do this.
CREATE TABLE #Temp (id INT, name VARCHAR(25))
INSERT INTO #Temp VALUES (1, 'A30F1'), (2, 'B51R9'), (3, 'L1721'), (4, 'A')
SELECT SUBSTRING(REPLACE(
0x00 + CAST(CAST(name AS NVARCHAR(25)) AS BINARY(50)), CHAR(0), '0,')
, 3
, LEN(name) * 3 - 1)
FROM #Temp
returns
0A,03,00,0F,01
0B,05,01,0R,09
0L,01,07,02,01
0A
This takes advantage of the fact that the binary representation of the nvarchar and varchar is the same for this limited character set except for padding out with 0x00
'A30F1' -> 0x4133304631
N'A30F1' -> 0x41003300300046003100